From the above identified prior patents, it will be seen that various arrangements for metallurgical cooling panel constructions have been utilized to improve the efficiency of the metallurgical cooling system and hence, attempt to prolong the life of the metallurgical heating furnace. In general, one type of water cooled panel includes the cast metal or solid metal panel type and another type relates to a fabricated panel construction commonly referred to as a water-box. Typically, the water-boxes are fabricated with cooling water inlet and outlet ports which enable cooling water to flow through a selective predetermined path formed in the box for cooling purposes. In some instances, the water-box type cooling panels have been provided with various exterior retention designs to enhance the refractory or slag build-up on the "hot face" of the cooling panel to retain the heat within the furnace. For example, staggered tubes are disclosed in U.S. Pat. No. 4,455,017, fins are disclosed in U.S. Pat. No. 4,351,055, anchors are disclosed in U.S. Pat. No. 4,241,232 and studs are disclosed in U.S. Pat. No. 4,206,312.
In applicant's prior U.S. Pat. No. 3,445,101, a fume hood cooling panel for a basic oxygen steel making furnace is disclosed which utilizes corrugations and in conjunction with fins for dividing the main channel between the cold face and hot face into a number of sub-channels. Similarly, prior U.S. Pat. No. 3,661,372 discloses a fume hood for a basic oxygen furnace which utilizes an undulating front plate in conjunction with a flat back plate and with vane divider bars or plates that are welded to the front and back plates to form internal fluid flow channels within the panel. Accordingly, such prior designs do not disclose a hot-face panel construction wherein the hot face and cold face join and hence, contact on the cold face plate to provide channels for transmitting of a cooling media.
Accordingly, the present invention provides various advantages and efficiencies which are not present in prior cooling panel designs particularly for electric arc furnace applications. Specifically, by the forementioned hot and cold face contact via the corrugations, the interior welds are protected from temperature fluctuations thereby to minimize distortion and/or shrinkage of the panel. Unlike the prior fume hood designs, the improved design of the present invention provides cooling water channels which eliminates the need for special baffles, fins, dividers, vanes and the like and hence, provides a substantial cost savings. Accordingly, the cold-side flat plate is tangentially formed from the center line of the panel so as to provide a structure which can accommodate any curvature of the furnace shell. In the invention, the panel corrugations are made of a heavy gauge steel while the cold side flat plate is plug welded to the corrugated hot face panel so as to give a rigid construction with the welds protected from the high furnace temperatures, as aforesaid.
Also, in the invention the relatively deep vertical grooves formed in the hot face panel by the corrugated design in combination with the retention elements maximize the build-up of refractory (i.e. slag and/or gunning material) on the hot face surface. It has been found that the vertical corrugations act to resist panel warpage, cyclic surface expansion, and impact damage from heavy scrap charges. With the corrugations on the hot face surface, it is believed that there occurs a local plate expansion within the individual loop segments (between plugs and contact to the cold face), rather than a total hot face expansion. Still further, this construction and arrangement provides a great number of possibilities for access hole sizes and locations for furnace entry of lances, probes, oxy fuel burners and the like.
Other advantages and objects of the present invention will become apparent as the following description proceeds when taken in conjunction with the specification and drawings.